The invention relates to a blocking apparatus for blocking and/or sealing off a line for transporting—preferably hot—media, in particular dust-laden gases, preferably for blocking and/or sealing off a line for transporting hot gases which may be laden with solid particles, having a movable closure body and at least one sealing element, in particular a seat ring, against which the closure body bears in the blocking position, and having a device for rotating the closure body about an axis of rotation, in particular a shaft, to which the closure body is connected.
The prior art has disclosed various blocking apparatuses which are of only limited use for transporting a hot gas, optionally laden with solid particles. The hot gas laden with solid particles generally severely impairs the closing and/or sealing action of the blocking apparatuses which are known from the prior art.